Osmotic devices have demonstrated utility in delivering useful active agents such as medicines, nutrients, food products, pesticides, herbicides, germicides, algaecides, chemical reagents, and others known to those of ordinary skill to an environment of use in a controlled manner over prolonged periods of time. Known devices include tablets, pastilles, pills or capsules and others that use osmotic pressure to control the release of the active agent contained in the core of the osmotic device. Some osmotic devices may also include layers comprising one or more materials that are subject to erosion or that slowly dissolve in the environment of use thereby gradually dispensing the active agent. Known devices generally suffer from an inability to dispense all or substantially all the active agent from the core prior to the loss of osmotic pressure that occurs at osmotic equilibrium.
U.S. Pat. No. 4,088,864 to Theeuwes et al. (“Theeuwes et al. '864) discloses a high speed process for forming outlet passageways in the walls of osmotic devices for release of the contents of the osmotic device comprising: a) moving the pills in succession along a predetermined path at a predetermined velocity; b) tracking the moving pills seriatim at said velocity with a laser of a wavelength which is absorbable by said walls by oscillating the optical path of the laser back and forth over a predetermined section of the pill path at said velocity; c) firing the laser during said tracking; d) adjusting the laser beam dimension at said wall, the laser power and the firing duration such that the laser beam is capable of piercing the wall; and e) forming, with the laser beam, an outlet passageway 4 to 2000 microns in diameter in the wall. Theeuwes et al. '864 does not disclose an osmotic device which membrane ruptures even though it has a preformed aperture in the membrane.
Theeuwes et al. '864 also discloses an apparatus for forming outlet passageways in the walls of osmotic devices for release of the contents of the osmotic device comprising: a) a support frame; b) a laser operating in a pulse mode; c) an optical pill tracking mechanism; d) a rotary pill indexer; and e) an electrical power supply to supply and control power for the laser, the tracking mechanism, and the indexer. Theeuwes et al. '864 does not disclose an osmotic device which membrane ruptures even though it has a preformed aperture in the membrane.
U.S. Pat. No. 4,014,334 to Theeuwes et al. (“Theeuwes et al. '334”) discloses an osmotic device for the controlled and continuous delivery of a drug wherein the device comprises: a) a core containing a drug and an osmotic agent; b) a semipermeable laminate, surrounding the core, which includes an external semipermeable lamina and an internal semipermeable lamina; and c) a passageway which communicates the core with the exterior of the device. The two semipermeable laminae maintain their chemical and physical integrity in the presence of the drug and fluid from the environment. The passageway of Theeuwes et al. '334 includes a passageway, orifice or bore through the laminate formed by mechanical procedures, or by eroding an erodible element, such as a gelatin plug, in the environment of use. Theeuwes et al. '334 does not disclose an osmotic device which membrane ruptures even though it has a preformed aperture in the membrane.
U.S. Pat. No. 4,576,604 to Guittard et al. (“Guittard et al. '604”) corresponds to Argentina Patent No. 234,493 and discloses several different embodiments of an osmotic device having a drug in the core and at least one lamina surrounding the core. Specifically, one embodiment of the osmotic device comprises: a) a core containing a drug formulation which can include an osmotic agent for controlled release of the drug; b) a semipermeable wall comprising an inner semipermeable lamina, a middle microporous lamina, and an outer water soluble lamina containing drug; and c) a passageway which communicates the core with the exterior of the device. Guittard et al. '604 does not disclose an osmotic device which membrane ruptures even though it has a preformed aperture in the membrane.
U.S. Pat. No. 4,673,405 to Guittard et al. (“Guittard et al. '405”) discloses an osmotic device comprising: a) a core, or compartment, containing a beneficial agent; b) an inert semipermeable wall containing a beneficial agent surrounding the core; and c) at least one passageway in the wall of the osmotic device which is formed when the osmotic device is in the fluid environment of use and the fluid contacts and thus releases the beneficial agent in the wall, wherein the formed passageway communicates with the compartment in the osmotic device and the exterior of the device for dispersing the beneficial agent from the compartment when the device is in the fluid environment of use. Guittard et al. '405 discloses the use of an erodible element to form the passageway; however, it does not disclose an osmotic device which membrane ruptures even though it has a preformed aperture in the membrane.
U.S. Pat. No. 5,558,879 to Chen et al. (“Chen et al. '879”) discloses a controlled release tablet for water soluble drugs in which a passageway is formed in the environment of use, i.e., the GI tract of a person receiving the formulation. Specifically, the controlled release tablet consists essentially of: a) a core containing a drug, 5-20% by weight of a water soluble osmotic agent, a water soluble polymer binder and a pharmaceutical carrier; and b) a dual layer membrane coating around the core consisting essentially of: (1) an inner sustained release coating containing a plasticized water insoluble polymer and a water soluble polymer; and (2) an outer immediate release coating containing a drug and a water soluble polymer. Although Chen et al '879 discloses the formation of a passageway in a controlled release tablet in an environment of use to form an osmotic tablet. Chen et al. do not disclose a coated controlled release device which membrane ruptures even though it has a preformed aperture in the membrane.
U.S. Pat. No. 4,810,502 to Ayer et al. (“Ayer et al. '502”) discloses an osmotic dosage form for delivering pseudoephedrine (Ps) and brompheniramine (Br) which comprises: a) a core containing Ps and Br; b) a wall surrounding the core comprising cellulose acylate and hydroxypropylcellulose; c) a passageway in the wall for delivering the drug; and d) a lamina on the outside of the wall comprising Ps, Br, at least one of hydroxypropylcellulose and hydroxypropyl methylcellulose, and poly(ethylene oxide) for enhancing the mechanical integrity and pharmacokinetics of the wall. Ayer et al. '502 does not disclose a coated controlled release device which membrane ruptures even though it has a preformed aperture in the membrane.
U.S. Pat. No. 4,801,461 to Hamel et al. (“Hamel et al. '461”) discloses an osmotic dosage form for delivering pseudoephedrine (Ps). Specifically, the osmotic dosage form comprises: a) a core containing varying amounts of Ps; b) a semipermeable wall surrounding the core comprising varying amounts of cellulose acetate or cellulose triacetate and varying amounts of hydroxypropylcellulose; c) a passageway in the wall for delivering the drug from the core; and optionally d) a lamina on the outside of the wall comprising Ps. The core can also contain one or more of sodium chloride, microcrystalline cellulose, hydroxypropyl methylcellulose, magnesium stearate, and poly(vinylpyrrolidone). The passageway of this device can extend through the semipermeable wall alone or through both the semipermeable wall and the outer lamina. The passageway also includes materials that erode or leach in the environment of use. A variety of erodible materials are listed as suitable for use in forming the passageway. Hamel et al. '461 does not, however, disclose a coated controlled release device which membrane ruptures even though it has a preformed aperture in the membrane.
U.S. Pat. No. 5,681,584 to Savastano et al. (“Savastano et al. '584”) discloses a controlled release drug delivery device comprising: a) a core containing a drug, an optional osmotic agent and optional excipients; b) a delayed release jacket comprising at least one of a binder, an osmotic agent and a lubricant surrounding the core; c) a semipermeable membrane surrounding the delayed release jacket and optionally having a passageway; d) a drug-containing layer either on the outside of the semipermeable membrane or between the semipermeable membrane and the delayed release jacket; and e) an optional enteric coat either on the outside of the drug-containing layer, between the drug-containing layer and the semipermeable membrane or on the outside of the semipermeable membrane when the drug-containing layer is between the delayed release jacket and the semipermeable membrane. Thus, the device of Savastano et al. '584 does not rupture even though it has a preformed passageway.
U.S. Pat. No. 6,004,582 to Faour et al. (Faour et al. '582) discloses a multi-layered osmotic device comprising a core surrounded by a semipermeable membrane having a preformed hole in it. The hole is subsequently plugged by an inert erodible water soluble coating and then covered with a water soluble drug-containing coating. This patent does not disclose a coated controlled release device which membrane ruptures even though it has a preformed aperture in the membrane.
U.S. Pat. No. 5,873,793 to Emerton et al. (Emerton et al. '793) and U.S. Pat. No. 5,376,771 to Roy (Roy '771) disclose laser apparatuses capable of simultaneously forming a plurality of holes on the semipermeable membrane of an osmotic device. These patents do not disclose a coated controlled release device which membrane ruptures even though it has a preformed aperture in the membrane.
Additional exemplary osmotic devices for the controlled delivery of active agents are described in U.S. Pat. No. 3,845,770 and Argentina Patent No. 199,301 which disclose an osmotic device formed by a wall that surrounds a compartment-housing agent. The wall has a passageway or orifice that links the compartment to the environment of use. The wall is made of semipermeable material that is semipermeable to an external fluid and impermeable to an active agent within the device. Neither of these patents discloses a coated controlled release device which membrane ruptures even though it has a preformed aperture in the membrane.
U.S. Pregrant Patent Publication No. 2002/0099361 to Faour discloses an osmotic device having a preformed passageway that increases in size during use by rupture of the membrane surrounding the preformed passageway. The membrane is optionally etched to promote rupture of the membrane along a predetermined path and/or to a predetermined extent. The '361 publication does not disclose a coated controlled release device which membrane ruptures at a location spaced apart from or away from the preformed aperture in the membrane. The '361 publication only discloses rupture of the membrane on the edge defining the preformed passageway in the membrane.
While the prior art discloses a wide variety of release mechanisms used in osmotic devices and coated controlled release devices, no single release mechanism provides a coated controlled release dosage form comprising a preformed passageway wherein the coating of the dosage form ruptures at a location spaced away from the preformed passageway during use of the device so that controlled delivery of all or substantially all the amount of active agent is provided or so that the rate of release of the drug increases over time.